sour
adj. A2 Elementary US //ˈsaʊɝ// UK //sˈaʊə// sour
adj. having a sharp taste like a lemon or vinegar. It is the opposite of sweet.
adj. having an acid or tart taste, typically characteristic of citrus fruits or fermented substances.
The milk smells sour because it is old.
She added a little sugar to the dressing because the lemon juice was too sour for her guests.
The fermentation process gives the sourdough bread its characteristic tangy flavor, which contrasts sharply with the mildness of the butter.
Usage
Commonly used to describe food and drink, but can also describe a person's mood or a situation that has gone wrong.